fXmlRpc\Exception\MissingExtensionException::extensionMissing PHP Метод

    public static function extensionMissing($extension)
    {
        return new static(sprintf('PHP extension "ext/%s" is required but not installed', $extension));
    }

 public function __construct($validateResponse = true)
 {
     if (!extension_loaded('xmlreader')) {
         throw MissingExtensionException::extensionMissing('xmlreader');
     }
     $this->validateResponse = $validateResponse;
 }